CVE-2026-110673: high-severity vulnerability in Cpanel-JSON-XS
Cpanel::JSON::XS versions before 4.80 for Perl allow stack exhaustion via nested tagged values under allow_tags in decode_tag
Published · Updated
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.5epss 0.5%
Cpanel::JSON::XS versions before 4.80 for Perl allow stack exhaustion via nested tagged values under allow_tags in decode_tag.
With allow_tags, "(" starts a tagged value. Its tag and value are decoded recursively, and each can start another tagged value. Unlike arrays and objects, this nesting is not counted against max_depth.
A run of "(" bytes exhausts the C stack and triggers an uncatchable segmentation fault regardless of max_depth.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
Cpanel-JSON-XSRelated CVEs — Cpanel-JSON-XS
In the same product, most dangerous first.
CVE-2026-110674MEDIUMCpanel::JSON::XS versions from 4.33 before 4.80 for Perl miss duplicate non-ASCII bare keys, allowing type confusion under dupkeys_as_arrayref in decode_hvEPSS 0.5%CVE-2026-110685CRITICALCpanel::JSON::XS versions before 4.80 for Perl leak the decoded arguments of a tagged value when its THAW method dies in decode_tagEPSS 0.5%CVE-2026-110678HIGHCpanel::JSON::XS versions before 4.80 for Perl allow memory exhaustion by buffering incremental input past max_size in incr_parseEPSS 0.5%CVE-2026-110676HIGHCpanel::JSON::XS versions before 4.80 for Perl allow memory exhaustion by encoding exponent notation as full decimal digits under allow_bignumEPSS 0.5%CVE-2026-110672HIGHCpanel::JSON::XS versions before 4.80 for Perl leak the decoded key of an object rejected for a duplicate key or a missing colon in decode_hvEPSS 0.5%CVE-2026-110688HIGHCpanel::JSON::XS versions from 4.51 before 4.80 for Perl allow quadratic CPU use by revalidating the remaining buffer per value in incr_parseEPSS 0.5%